Separate soloist and choral parts on the same score

Hello,
I'd like to rewrite a score I have on paper but I'm facing some problems.

The piece is a song with some soloist parts and some choral parts, where there are quite a lot of measures that are performed by the soloist alone, without the chorus, and this wastes a lot of space on the score.

I've seen I can hide the pentagram on a per-measure, per-instrument basis, but first of all it's really time consuming, and furthermore it does not compress the layout, it simply leaves blank space where the empty (and hidden) measures are.

Is there any clever trick to solve this issue?

I thought about putting a vertical separator and drag it to a negative value, so that it would stash together instead of separating, but unfortunately that doesn't seem to seem to be allowed.

I've also thought about using negative values in the general distance settings, but then I'd have to put a lot of separators to bring back to normality the distances where I have the choral parts with the other voices.

Any hint would be really appreciated, thanks a lot for your attention!